Plate or element for storage batteries.



UNITED STATES PATEQT, @rricn.

,ELMER A. SPERRY, OF CLEVELAND, OHIO.

P'LATE OR ELEMENT FOR STORAGE. BATTERIES.

SPECIFICATION forming part of Letters Patent No. 660,228, dated October 23, 1900.

s td much as, 1900. Serial Fo.19,197. nstotwimm.)

To all whom. i't mny cancer-m" Be it known that I, Emma A. SPERRY, a citizen of the United States, residing at (loveland, in the county of Cuyahoga and State of 'Ohio, have invented certain new and useful Improvements in Plat-es or Elements for Storage Batteries, of which the following is" a specification. I

My invention is an improvement in the plates or elements of secondary or storage batteries; and said invention consists in a plate r elementcomposed of a sustaining sheet or body of lead or other similar and equivalent material to which, as to one or both sides, is applied or in any suitable manner attached a mass consisting of a mechanical mixture of lead particles, oxids of lead, and an alkali-metal salt moistened with a solution of a hydroxid of the alkali metals.

The following is the method of making a secondary-battery plate or element according to my invention: I first take the oxid or mixture of oxids of lead and intimately mix therewith the salt constituents consisting of sulfate or a mixture of the sulfate and phosphate of one or more of the alkali bases, potassium or ammonium preferred. This mixture is then moistened with distilled water and is mixed with finely-divided metallic lead-such, for example, as precipitated lead, which after precipitation should be kept in a suitable vessel under water until used. The mixture of the lead, the oxid or oxide, and the alkali-- metal salt or salts is diluted until it reaches the consistency of thick dough, and while being vigorously stirred there isadded a solu' tion of hydroxid ofau'alkali metal-such, for instance,'as liquid ammonia diluted to from three-fi fths to one-fourth with distilled water. When the mass has been thus thinned down to a condition which permits it to be readily spread over a conducting plate or grid,it will be found to have the property of setting peculiar to cement. Itis then applied in any convenient manner to the plate or grid and is by preference caused to adhere thereto'as a closely-coherentmass compacted by pressure in a mold. .The mold consists of a heavy separable steel frame adapted to contain a retaining grid 01'- support. When the'pl'ate or grid, with an attached mass of the composition, is placed in the mold, it is immediable press; after which it is removed from the mold and set on edge to dry. I have found that the open airor the suns heutis the, best means of drying. I have also found that the heavy toggle-press is more suitable than the hydraulic press for this work on account of the more rapid action and the quickness with which the maximum pressures are reached, while with a press of sullicient capacity the final pressu res are equal to those obtained in the hydraulic press. When dry, the plates, by the action of an electric current'in a suitable bath, are formed, after which they are grouped and charged in the well-known from eighty to eighty-five per cent. of fiuelydivided lead, from fifteen to'twenty per cent.

of the oxi d of lead, and an admixture of a salt, such as sulfate of ammonium, amounting to about one twenty-fifth of the whole mass.

By following the above directions plates will be produced which after being formed will be found to possess a density much superior to those heretofore used and which have the further merit of containing a minimum of foreign material, there being m cally nothing present which does not contribute directly to increasing their capacity as battery elements.

I have found as a result of the use of the alkalisalts above described that while they are of themselvesinert they appear-to have aver-y important and twofold function, first, by dissolvingont during the process of forming, thereby facilitating the penetration of the electrolyte and the electrical disintegration of the metallic substance of the element, and,

second, in causing the active material while being electrolytically produced to set or ately subjected to heavy pressure in asuit harden rather than to soften, as is the case with all plates formed by the Plant process.

It will readilybe understood that while the details of the invention and process have been described with more or less minnteness yet the invention should not be limited to the exact methods and details described. For ex I do not claim herein the process of menu:

fsctu ring plates or elements of storage batteries herein described, having madethis the subject of another application filed April 13, 1900,. Serial No. 12,699.

Having now described my invention, who I claim is-- 1. The material herein described for the plates or elements of storage batteries coni sisting of a set' mass, composed of an intimate mixi u re of an alkali-metal salt, lead oxid, and

finely-divided lead, moistened with a solution of a'hydroxid of the alkali metals. v

2. A storage-batteryielernent consisting of a supporting grid or plate having a coating v attached thereto, said coating primarily com- 3. As an article'of man nfactnre, an element v for batteries consisting of a snpportim grid or plate upon and into wh ch is pressed set -fmaterial consistingof a-set mass composed of an intimate mixture of alksli metal salt, lead oxid and finely-divided lead, moistened with a solution of a hydroxid of the alkali metals,

' ELMEB La SPERRY.

Witnesses:

M. Lawson Dyna, BENJAMIN MILLER. 

